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This article will explain in detail how the nine extremely powerful JavaScript skills are, and the content of the article is of high quality, so the editor will share it for you as a reference. I hope you will have a certain understanding of the relevant knowledge after reading this article.

The so-called hacker method is a continuous improvement and iterative construction method. Programmers with the spirit of hacker believe that there is always room for improvement and that nothing is perfect. Each piece of code has room for further optimization, and each operation has a more convenient skill.

Here are some very powerful JavaScript hack techniques.

1. Replace All

We know that the string.Replace () function will only replace the first item.

You can replace everything by adding / g to the end of the regular expression.

Var example = "potato potato"; console.log (example.replace (/ pot/, "tom")); / / "tomato potato" console.log (example.replace (/ pot/g, "tom")); / / "tomato tomato"

two。 Extract unique valu

We can use the Set object and the Spread operator to create a new array that removes duplicate values.

Var entries = [1, 2, 2, 3, 4, 5, 6, 6, 7, 7, 8, 4, 2, 1] var unique_entries = [... new Set (entries)]; console.log (unique_entries); / / [1,2,3,4,5,6,7,8]

3. Convert a number to a string

All we need to do is use the concatenation operator with empty quotes.

Var converted_number = 5 + "; console.log (converted_number); / / 5 console.log (typeof converted_number); / / string

4. Convert a string to a number

Use the + operator.

Please note the usage here, because it only applies to "string numbers".

The_string = "123"; console.log (+ the_string); / / 123the_string =" hello "; console.log (+ the_string); / / NaN

5. Randomly arranging elements in an array

I line up at random every day.

Var my_list = [1,2,3,4,5,6,7,8,9]; console.log (my_list.sort (function () {return Math.random ()-0.5})); / / [4,8,2,9,1,3,6,5,7]

6. Flattened multidimensional array

Just use the Spread operator.

Var entries = [1, [2, 5], [6, 7], 9]; var flat_entries = [] .concat (....); / / [1, 2, 5, 6, 7, 9]

7. Short circuit condition

For example:

If (available) {addToCart ();}

You can shorten it simply by using variables and functions:

Available & & addToCart ()

8. Dynamic attribute name

I always thought I had to declare an object before I could assign a dynamic property.

Const dynamic = 'flavour'; var item = {name:' Coke', [dynamic]: 'Cherry'} console.log (item); / / {name: "Coke", flavour: "Cherry"}

9. Resize / empty the array using length

It's basically the length that overrides the array.

If we want to resize the array:

Var entries = [1,2,3,4,5,6,7]; console.log (entries.length); / / 7 entries.length = 4; console.log (entries.length); / / 4 console.log (entries); / / [1,2,3,4]

If we want to empty the array:

Var entries = [1, 2, 3, 4, 5, 6, 7]; console.log (entries.length); / / 7 entries.length = 0; console.log (entries.length); / / 0 console.log (entries); / / [] on how the 9 extremely powerful JavaScript skills are shared here, I hope the above content can help you to learn more knowledge. If you think the article is good, you can share it for more people to see.

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